Characterization of two types of yeast ribosomal DNA genes (original) (raw)
Related papers
Characterization of yeast ribosomal DNA fragments generated by EcoR1 restriction endonuclease
Molecular and General Genetics, 1976
The action of Escherichia coli restriction endonuclease R1 (EcoR1) on DNA isolated from Saccharomyces cerevisiae (strain MAR-33) generates three predominent homogenously sized DNA fragments (species of 1.8, 2.2 and 2.5 kilo nucleotide base pairs (KB). Many DNA species of molecular weight greater than 2 million daltons can be recognized upon incomplete EcoR1 digestion of yeast DNA. Four additional DNA species ranging from 0.3–0.9 KB can be identified as the second major class of EcoR1-yeast DNA products. Hybridization with radioactive ribosomal RNA (rRNA) and competition with nonradioactive rRNA show that of the three predominent EcoR1-yeast DNA species, the 2.5 KB species hybridizes only with the 25S rRNA while the lighter 1.8 KB species hybridizes with the 18S rRNA. The intermediate DNA species of 2.2 KB hybridizes to a small extent with the 25S rRNA and could be a result of the presence of the 2.5 KB DNA species. The mass proportions and hybridization values of these 3 DNA species account for about 60% of the total ribosomal DNA (rDNA). The 5EcoR1-yeast DNA species of less than 0.9 KB (4 major and 1 minor species) hybridize to varying degrees with the 2 rRNA and can be grouped in two classes. In one class there are 3 DNA species that hybridize exclusively with the 18S rRNA. In the second class there are 2 DNA species that besides hybridizing predominently with the 25S rRNA also hybridize with the 18S rRNA. The 7 EcoR1-yeast DNA species (excluding the 2.2 KB DNA species) that hybridize with the two rRNA account for nearly a 5 million dalton DNA segment, which is very close to the anticipated gene size of rRNA precursor molecule. If the 2.2 KB DNA species is a part of the rDNA that is not transcribed or 5 sRNA then the cistron encoding the rRNA in S. cerevisiae has at least 8 EcoR1 recognition sites resulting in 8 DNA fragments upon digestion with the EcoR1. Consideration is given to the relationship of the rRNA species generated by EcoR1 digestion and the chromosomes containing ribosomal cistrons.
A comparison of yeast ribosomal protein gene DNA sequences
Nucleic Acids Research, 1984
The DNA sequences of eight yeast ribosomal protein genes have been compared for the purpose of identifying homologous regions which may be involved in the coordinate regulation of ribosomal protein synthesis. A 12 bp homology was identified in the 5' DNA sequence preceding the stuctural gene for 6 out of 8 yeast ribosomal protein genes. In each case the homologous sequence was found at a position approximately 300 bp preceding the transcription start of the ribosomal protein gene. This homology was not identified in any non-ribosomal protein gene examined. Additional homologies between ribosomal protein genes were identified in the transcribed regions, including the untranslated 5' and 3' DNA regions flanking the coding regions. © I RL Press Limited, Oxford, England.
Archives of Biochemistry and Biophysics, 1970
Hybridization in solution was used to investigate the sequence homology between DNA and several high molecular weight species of Saccharomyces carlsbergensis. In agreement with others, about 1.3 and 0.770 of the DNA was found to be homologous respectively to the 265 and 175 ribosomal RNA components. Yeast ribosomal RNA is transcribed from a satellite with a buoyant density slightly higher (1.703) than main yeast DNA (1.698). The experiments indicate that the satellite contains some DNA other than that homologous to ribosomal RNA. Other experiments showed that the RNA synthesized in the presence of cycloheximide is a transcript of at least 20'% of the genome.
Transcription of Saccharomyces cerevisiae Ribosomal DNA in Vivo and in Vitro
Proceedings of The National Academy of Sciences, 1974
In vivo, ribosomal RNA of Saccharomyces cerevisiae is transcribed from the light strand of γ DNA. In vitro, γ DNA is transcribed with equal efficiency by both of the yeast nuclear RNA polymerases, polymerase I and polymerase II; however the RNA products synthesized by the two enzymes differ from each other both in size and in the relative composition of guanine and cytosine. RNA synthesized by polymerase I hybridizes preferentially to the light strand, while that synthesized by polymerase II hybridizes equally well to either strand. Selective transcription of the light strand of the ribosomal DNA also occurs when high-molecular-weight total nuclear DNA is used as template.
Distribution of Ribosomal Ribonucleic Acid Cistrons Among Yeast Chromosomes
Journal of Bacteriology
High-molecular-weight deoxyribonucleic acid (DNA) of Saccharomyces carls bergensis has been fractionated by sucrose density gradient centrifugation. The main DNA fraction has an average molecular weight of about 500 × 10 6 . A major fraction of the DNA molecules containing sequences homologous to ribosomal ribonucleic acid (RNA) sediments as material of this molecular weight. The remainder sediments as material of a molecular weight of about 250 × 10 6 . The latter fraction contains relatively more ribosomal RNA cistrons than the former. Studies on the buoyant density of high-molecular-weight DNA homologous to ribosomal RNA have led to the conclusion that the ribosomal RNA cistrons occur in groups attached to a relatively large amount of nonribosomal RNA and suggest that ribosomal RNA cistrons are distributed over a number of yeast chromosomes.
Isolation and characterization of twenty-three ribosomal proteins from large subunits of yeast
Biochemistry, 1979
Twenty-three polymorphic microsatellite loci were isolated from Schizothorax macropogon and were characterized in 42 individuals collected from the Yarlung Tsangpo River in Tibet, China. The number of alleles per locus ranged from 5 to 32 with an average of 20.17. The expected heterozygosity and Shannon-Wiener diversity index ranged from 0.709 to 0.951 and from 1.421 to 3.183, respectively. These microsatellite loci will be valuable for the evaluation of genetic diversity and population genetic structure of S. macropogon.
Chromosomal DNA preparation from yeasts of biotechnological importance
Biotechnology Techniques, 1996
Yeast chromosomal DNA was prepared under different conditions. Treatment of intact cells with proteinase I( (1 mg/ml) resultes in appropriate electrophoretic karyotypes; when protoplasts were formed III s&r, the presence of both sodium lauroylsarcosine and EDTA was essential. Further, the duration of cell wall lysis (12 h) and the concentrations of lytic enzymes (0.5% snail enzyme and 0.25% Novozym)had to be kept at a minimum.